javascriptApps/pong.html at main · develectro/javascriptApps · GitHub

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<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Pong Game</title>
    <style>
        body {
            display: flex;
            justify-content: center;
            align-items: center;
            height: 100vh;
            margin: 0;
            background-color: #333; /* Darker background for less eye strain */
            font-family: Arial, sans-serif;
        }
        canvas {
            border: 2px solid #fff; /* White border for the canvas */
            background-color: #000; /* Black playing field */
            box-shadow: 0 0 20px rgba(255, 255, 255, 0.3); /* Subtle glow */
        }
    </style>
</head>
<body>
    <canvas id="pongCanvas"></canvas>

    <script>
        const canvas = document.getElementById('pongCanvas');
        const context = canvas.getContext('2d');

        // Game settings
        canvas.width = 800;
        canvas.height = 600;

        const paddleWidth = 15;
        const paddleHeight = 100;
        const ballRadius = 10;
        const playerPaddleSpeed = 8;
        const aiPaddleSpeed = playerPaddleSpeed * 0.6; // AI is a bit slower

        // Colors
        const PADDLE_COLOR = "white";
        const BALL_COLOR = "white";
        const NET_COLOR = "rgba(255, 255, 255, 0.5)"; // Semi-transparent net
        const SCORE_COLOR = "white";
        const BACKGROUND_COLOR = "black";

        // Player paddle (right side, controlled by arrows)
        const playerPaddle = {
            x: canvas.width - paddleWidth - 30, // A bit more offset from the edge
            y: canvas.height / 2 - paddleHeight / 2,
            width: paddleWidth,
            height: paddleHeight,
            dy: 0, // direction of movement
            score: 0
        };

        // AI paddle (left side)
        const aiPaddle = {
            x: 30, // A bit more offset from the edge
            y: canvas.height / 2 - paddleHeight / 2,
            width: paddleWidth,
            height: paddleHeight,
            score: 0
        };

        // Ball
        const ball = {
            x: canvas.width / 2,
            y: canvas.height / 2,
            radius: ballRadius,
            speed: 5,
            dx: 5, // direction x
            dy: 5  // direction y
        };

        // --- Drawing Functions ---
        function drawRect(x, y, w, h, color) {
            context.fillStyle = color;
            context.fillRect(x, y, w, h);
        }

        function drawCircle(x, y, r, color) {
            context.fillStyle = color;
            context.beginPath();
            context.arc(x, y, r, 0, Math.PI * 2, false);
            context.closePath();
            context.fill();
        }

        function drawText(text, x, y, color, fontSize = "60px", font = "Consolas, 'Courier New', monospace", textAlign = "center", textBaseline = "middle") {
            context.fillStyle = color;
            context.font = `${fontSize} ${font}`;
            context.textAlign = textAlign;
            context.textBaseline = textBaseline;
            context.fillText(text, x, y);
        }

        function drawNet() {
            for (let i = 0; i <= canvas.height; i += 20) { // Dashes are a bit longer
                drawRect(canvas.width / 2 - 1.5, i, 3, 10, NET_COLOR); // Slightly thicker net
            }
        }

        // --- Input Handling (Arrow Keys for Player Paddle) ---
        document.addEventListener('keydown', function(event) {
            switch(event.key) {
                case 'ArrowUp':
                    playerPaddle.dy = -playerPaddleSpeed;
                    break;
                case 'ArrowDown':
                    playerPaddle.dy = playerPaddleSpeed;
                    break;
            }
        });

        document.addEventListener('keyup', function(event) {
            switch(event.key) {
                case 'ArrowUp':
                case 'ArrowDown':
                    playerPaddle.dy = 0;
                    break;
            }
        });

        // --- Update Functions ---
        function updatePlayerPaddle() {
            playerPaddle.y += playerPaddle.dy;
            // Keep player paddle within canvas bounds
            if (playerPaddle.y < 0) {
                playerPaddle.y = 0;
            } else if (playerPaddle.y + playerPaddle.height > canvas.height) {
                playerPaddle.y = canvas.height - playerPaddle.height;
            }
        }

        function updateAiPaddle() {
            const aiPaddleCenter = aiPaddle.y + aiPaddle.height / 2;
            const ballCenterY = ball.y;

            // AI tries to follow the ball with a small dead zone to prevent jittering
            const deadZone = 10; // Pixels
            if (Math.abs(aiPaddleCenter - ballCenterY) > deadZone) {
                if (aiPaddleCenter < ballCenterY) {
                    aiPaddle.y += aiPaddleSpeed;
                } else if (aiPaddleCenter > ballCenterY) {
                    aiPaddle.y -= aiPaddleSpeed;
                }
            }

            // Keep AI paddle within canvas bounds
            if (aiPaddle.y < 0) {
                aiPaddle.y = 0;
            } else if (aiPaddle.y + aiPaddle.height > canvas.height) {
                aiPaddle.y = canvas.height - aiPaddle.height;
            }
        }

        function resetBall(serveDirectionX) {
            ball.x = canvas.width / 2;
            ball.y = canvas.height / 2;
            ball.speed = 5; // Reset speed

            // Angle for serving, slightly randomized but not too vertical
            let angle = (Math.random() * Math.PI / 3) - (Math.PI / 6); // -30 to +30 degrees

            ball.dx = serveDirectionX * ball.speed * Math.cos(angle);
            ball.dy = ball.speed * Math.sin(angle);

            // Ensure the ball doesn't get stuck going too horizontally or vertically initially
            if (Math.abs(ball.dy) < 1) {
                ball.dy = (Math.random() > 0.5 ? 1 : -1) * 1.5;
            }
            if (Math.abs(ball.dx) < 2) { // Ensure minimum horizontal speed
                 ball.dx = serveDirectionX * 2;
            }
        }

        function collides(b, p) { // b for ball, p for paddle
            const bTop = b.y - b.radius;
            const bBottom = b.y + b.radius;
            const bLeft = b.x - b.radius;
            const bRight = b.x + b.radius;

            const pTop = p.y;
            const pBottom = p.y + p.height;
            const pLeft = p.x;
            const pRight = p.x + p.width;

            return bRight > pLeft && bLeft < pRight && bBottom > pTop && bTop < pBottom;
        }

        function updateBall() {
            ball.x += ball.dx;
            ball.y += ball.dy;

            // Ball collision with top and bottom walls
            if (ball.y + ball.radius > canvas.height || ball.y - ball.radius < 0) {
                ball.dy *= -1;
                // Clamp position to prevent sticking to walls
                if (ball.y + ball.radius > canvas.height) {
                    ball.y = canvas.height - ball.radius;
                } else if (ball.y - ball.radius < 0) {
                    ball.y = 0 + ball.radius;
                }
            }

            // Determine which paddle is relevant for collision
            let paddleToHit = (ball.x < canvas.width / 2) ? aiPaddle : playerPaddle;

            if (collides(ball, paddleToHit)) {
                let collidePoint = (ball.y - (paddleToHit.y + paddleToHit.height / 2));
                collidePoint = collidePoint / (paddleToHit.height / 2); // Normalize to -1 to 1

                // Max angle of deflection: 45 degrees (PI/4)
                let angleRad = (Math.PI / 4) * collidePoint;

                if (paddleToHit === aiPaddle) { // Hit AI paddle (left one)
                    ball.dx = ball.speed * Math.cos(angleRad); // Ball moves right
                    ball.x = aiPaddle.x + aiPaddle.width + ball.radius; // Reposition to avoid sticking
                } else { // Hit player paddle (right one)
                    ball.dx = -ball.speed * Math.cos(angleRad); // Ball moves left
                    ball.x = playerPaddle.x - ball.radius; // Reposition
                }
                ball.dy = ball.speed * Math.sin(angleRad);

                ball.speed += 0.25; // Increase ball speed slightly after each hit
                if (ball.speed > 15) ball.speed = 15; // Max speed cap
            }

            // Scoring
            if (ball.x + ball.radius < 0) { // Ball went past left edge (AI paddle side)
                playerPaddle.score++;
                resetBall(-1); // Serve towards AI (who just lost point, so dx is negative)
            } else if (ball.x - ball.radius > canvas.width) { // Ball went past right edge (Player paddle side)
                aiPaddle.score++;
                resetBall(1);  // Serve towards Player (who just lost point, so dx is positive)
            }
        }

        // --- Game Loop ---
        function gameLoop() {
            // 1. Update game state
            updatePlayerPaddle();
            updateAiPaddle();
            updateBall();

            // 2. Render (draw) the game
            // Clear canvas (draw background)
            drawRect(0, 0, canvas.width, canvas.height, BACKGROUND_COLOR);

            // Draw net
            drawNet();

            // Draw paddles
            drawRect(playerPaddle.x, playerPaddle.y, playerPaddle.width, playerPaddle.height, PADDLE_COLOR);
            drawRect(aiPaddle.x, aiPaddle.y, aiPaddle.width, aiPaddle.height, PADDLE_COLOR);

            // Draw ball
            drawCircle(ball.x, ball.y, ball.radius, BALL_COLOR);

            // Draw scores
            drawText(aiPaddle.score.toString(), canvas.width / 4, 50, SCORE_COLOR);
            drawText(playerPaddle.score.toString(), 3 * canvas.width / 4, 50, SCORE_COLOR);

            // Call gameLoop again on the next frame
            requestAnimationFrame(gameLoop);
        }

        // --- Start the game ---
        resetBall(Math.random() > 0.5 ? 1 : -1); // Initial serve with random direction
        gameLoop();
    </script>
</body>
</html>